This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Structural biology of argonaute mediated RNA silencing. Structural biology of riboswitches and gene regulation. Structural biology of readers and erasers of histone marks.